P2634 Code - Fuel Transfer Pump Relay Control Circuit High Voltage
Quick Answer
The Engine Control Module (ECM) enables the secondary fuel pump relay when the primary fuel tank is below approximately 50 liters (13.2 gallons) and will run until the primary tank is filled to approximately 70 liters (18.5 gallons) or until the secondary tank is empty. Common causes include Faulty Secondary Fuel Pump Relay, Secondary Fuel Pump Relay harness is open or shorted, Secondary Fuel Pump Relay circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P2634 indicates Fuel Transfer Pump Relay Control Circuit High Voltage.
- Common causes
- Common causes include Faulty Secondary Fuel Pump Relay, Secondary Fuel Pump Relay harness is open or shorted, Secondary Fuel Pump Relay circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P2634 Description
The control module monitors the voltage on the fuel transfer pump relay control circuit. If the control module detects an incorrect voltage on the fuel transfer pump relay control circuit, a fuel transfer pump relay control Diagnostic Trouble Code (DTC) sets.
What are the Possible Causes of the DTC P2634?
- Faulty Secondary Fuel Pump Relay
- Secondary Fuel Pump Relay harness is open or shorted
- Secondary Fuel Pump Relay circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P2634?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P2634 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P2634 Audi — Fuel Pump 'B' Control Circuit High
- P2634 Buick — Fuel Transfer Pump Relay Control Circuit High Voltage
- P2634 Cadillac — Fuel Transfer Pump Relay Control Circuit High Voltage
- P2634 Chevrolet — Fuel Transfer Pump Relay Control Circuit High Voltage
- P2634 Dodge — Fuel Pump 'B' Control Circuit High
- P2634 Ford — Fuel Pump 'B' Control Circuit High
- P2634 GMC — Fuel Transfer Pump Relay Control Circuit High Voltage
- P2634 Lincoln — Fuel Pump 'B' Control Circuit High
- P2634 Mercury — Fuel Pump 'B' Control Circuit High
- P2634 Volkswagen — Fuel Pump 'B' Control Circuit High
Frequently Asked Questions about P2634 Code
No Frequently Asked Questions about P2634 Code found.
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